In the Garden:Upper South
July, 2010
Regional Report

New coneflower varieties, such as orange-flowered 'Tiki Torch,' offer many opportunities for ways to use them in the garden.

Whither the Purple Coneflower?

Purple coneflowers are one of our most beloved native perennials for the garden, what with their large, daisy-like flowers that bloom for a long period during summer, adaptability and ease of cultivation, tolerance to both heat and drought, and attractiveness to butterflies and bees. But have you noticed lately that purple coneflowers, aren't, well, purple anymore. Not that they were ever truly purple - more of a deep pink. Today, at garden centers, you'll see varieties in shades of yellow, gold, orange, mango, salmon, rose-red, lime-green and white (and what perfect partners these make with daylilies!). Plus, while the natural species, Echinacea purpurea, grows 3 to 4 feet tall, there are more compact, branching varieties now offered.

So what's up with the purple coneflower? First of all, let's just call it coneflower. Next, let's take a look at a little background.

The Botany of Coneflowers
The genus Echinacea is a member of the daisy, or sunflower, family and is native to the eastern and central United States. The nine species in the genus are found naturally growing on prairies and in open woodlands and savannas, with purple coneflower tolerating more shade and moisture than the others.

Herbaceous perennial plants, coneflowers usually have a rounded base of foliage arising from an underground rhizome, taproot or fibrous roots, with elongated flower stems. The blooms of coneflowers are composed of two distinct types of flowers - disk florets and ray florets. The colorful "petals" are the ray florets, while the prominent cone is composed of orange to brown disk florets. It is the spiny bracts protruding from the disk florets that gave rise to the genus name. The Greek word echinos means hedgehog.

Coneflowers are unable to self-pollinate, relying instead on insects or man. Most of the new hybrids are the result of crosses between purple coneflower (E. purpurea), yellow coneflower (E. paradoxa), and black Samson coneflower (E. angustifolia).

Shortcut to Choosing Coneflower Varieties
So now that there are dozens and dozens of coneflower varieties, what's a gardener to do? Some of us will just pick up whatever's available locally. Others will search mail-order nurseries for every one to add to the collection. As experience teaches us, some of these coneflowers will be great, others not so much. The Mt. Cuba Center, a native plant botanical garden near Wilmington, Delaware, offers gardeners a great shortcut to saving time, money, and effort with a three-year evaluation (2007-2009) of 43 cultivars and five species, determining their desirability for garden use based on flower display, growth habit, winter hardiness, adaptability, and resistance to insects and disease. Although there are new cultivars continually being introduced, Mt. Cuba's highly recommended picks will give you the advantage of having the most beautiful and reliable ones for your garden now.

Echinacea pallida - One of the species, this one bears flowers of pale to rosy-pink flowers, with the 3-inch narrow drooping petals resembling streamers. Plants can grow from 26 to 40 inches tall with an open, upright habit. These are especially effective in a meadow or naturalized planting.

Echinacea tennesseensis - The flowers of Tennessee coneflower are unique due to their narrow, upturned petals with notched tips. It is very drought tolerant. From Mt. Cuba comes this admonition, "It is important to note that this is a Federally Endangered Species and should only be purchased from nurseries with a valid US Fish and Wildlife permit to propagate and sell them. Alternatively, purchase E. tennesseensis 'Rocky Top'."

Since the start of Mt. Cuba's study in 2007, many new Echinacea cultivars have been introduced, and the Center has plans to continue evaluations. So a tip of the cap to them for helping us choose beautiful, easy-to-grow coneflowers for our gardens now and in the future.